JavaScript

Check if Integer Exists at JSON Path

Demonstrates how to get an integer value at a JSON path, and how to check to see if it exists. JavaScript

var success = false;

var json = new CkJsonObject();

// First build simple JSON..
json.UpdateInt("test.abc",100);

json.EmitCompact = false;
console.log(json.Emit());

// This is our JSON:
// {
//   "test": {
//     "abc": 100,
//   }
// }

var path = "test.notHere";

// The call to IntOf will return 0, because it's not present.
// But how do we know if it really was present, and the value was truly 0?
var val = json.IntOf(path);
console.log("val = " + val);

// We cannot use LastMethodSuccess because LastMethodSuccess only applies
// to methods that:
// - return a string
// - return a new Chilkat object, binary bytes, or a date/time.
// - returns a boolean status where true = success and false = failed.
// - returns an integer where failure is defined by a return value less than zero.
// The IntOf method fits none of these requirements, and therefore the LastMethodSuccess 
// is not a valid indicator..
var wasFound = json.LastMethodSuccess;
console.log("wasFound = " + wasFound + " (not a valid indicator)");

// Instead, if the returned value is 0, we can double-check to see if the member was truly there..
if (val == 0) {
    wasFound = json.HasMember(path);
    console.log("wasFound = " + wasFound);
    if (wasFound == true) {
        console.log("The value was present and is 0.");
    }
    else {
        console.log("no member is present at test.notHere");
    }

}
else {
    console.log("val = " + val);
}

// Alternatively, you could check to see if the member exists beforehand..
if (json.HasMember(path) == true) {
    console.log("val = " + json.IntOf(path));
}
else {
    console.log("no member at " + path);
}